Microelectromechanical systems (MEMS) devices are semiconductor devices with embedded mechanical components. MEMS sensor devices include, for example, pressure sensors, accelerometers, gyroscopes, microphones, digital mirror displays, micro fluidic devices, and so forth. MEMS sensor devices are used in a variety of products such as automobile airbag systems, control applications in automobiles, navigation, display systems, inkjet cartridges, and so forth.
Magnetic field sensors, also known as magnetometers, are widely used in a number of applications including in, for example, compass, security, and military applications, geophysics and space research, biomagnetism and medical applications, and non-destructive testing. Magnetic field sensors are typically based on semiconductor materials (e.g., Hall sensors, semiconductor magnetoresistors, and so forth) and ferromagnetic materials (e.g., ferromagnetic magnetoresistors and flux guides). Other magnetic field sensors utilize optical, resonant, and superconducting properties. Magnetic field sensors may be designed to sense magnetic fields along one or more mutually exclusive axes, typically referred to as the X-axis, Y-axis, and Z-axis.
Existing sensors for measuring parameters such as those mentioned above suffer from various limitations well known in the art. Examples of such limitations include excessive size and weight, inadequate sensitivity and/or dynamic range, cost, reliability and other factors. Thus, there continues to be a need for improved sensors, especially sensors that can be easily integrated with semiconductor devices and integrated circuits and manufacturing methods therefore.
The miniaturization of many modern applications make it desirable to shrink the physical size of electronic devices, integrate multiple components or devices into a single chip, and/or improve circuit layout efficiency. Ideally, such sensors should be manufactured in a cost effective manner which reduces the additional layout area or space the sensors consumes. It would be desirable to have a semiconductor-based device which includes MEMS sensor devices integrated with magnetic sensors on a single substrate, particularly where the MEMS sensor devices and the magnetic sensors are fabricated using the same process technology such that the devices and sensors are compatible with semiconductor device and integrated circuit structures and fabrication methods.